Thermostat control



Jam 27, 1931., R. s. TICE ET AL 1,790,121

THERMOSTAT CONTROL Filed Feb4 25, 1929 bmwwmwwmm/ Patented Jim. l?, i931L Y UNITED STATES PATENT OFFICE 'l REUBEN' S.\TIOE, OF MION'TEB'EY,v AND ARTHUR L. HOLCOMB, OF SAN J OSE, CALIFORNIA THERMOSTAT CONTROL Application led February 25, 1929. -Serial No. 342,851..

The present invention relates to improve- I ments in thermostat controls', and its object is to provide a particularly sensitive thermostat for controlling an electrical circuit including a current-consuming device, as, for instance, an electrical heater.

More particularly, it is proposed in the` present invention to utilize for the purpose of obtaining a sensitive thermostat two bimetallic spirals, the inner ends 'of which are mounted on spaced posts, while the outer ends are interconnected, preferably in such a man'- ner as to place both of the spirals under slight tension, which causes the connection to snap across a medial line under the influence of changes in temperature.

It is further proposed in the present invention to mount the posts in such a mannerv that by a slight turning motion of the same, the tension ot the two spirals may be changed, so that the same may be made to become responsive to different degrees of temperature.

It is further proposed to provide means allowing the spacing between the tWo posts to be changed for ad]ustment purposes.

Further objects and advantages of our invention will appear as the specification proceeds.

The preferred forms of our invention are illust-rated in the accompanying drawing, in which Figure 1 shows a top plan view of one form of thermostat;

Figure 2, a side elevation of the same',

Figure 3, a side elevation of a modified form of our thermostat; and

Fi ure 4, a top plan. view of the same.

W ile we have shown only the preferredA forms of the invention, we wish to have it understood that various changes or modilications may be made within the scope of the claims hereto attached without departing from the spirit of the invention.

In the forms shown in Figures 1 and 2, our.

thermostat consists of a base 1 of insulating material having mounted thereon, in spaced relation, two small plates 2 somewhat elongated in form, each fastened to the base by means of two screws 3 and 4, the latter of which extends through a slot 6 in the plate 2,

lso that'each plate ma be swung about the screw 3 as a pivot, W ile the screw 4 rides in the slot 6. Each of the plates 2 has extending upwardly from a central. section 'i a manner that normally their loose ends f would sli htly overla and therefore have to be slight y pushed Each for affecting the hinged. connection. The metals should be arranged in the two spirals in such a manner that after they have been connected, the same metals are presented on the same sides. The

post 'l'4 of veach spiral has an arm extending therefrom, and these two arms 11 and l2 are interconnected by means of a pin 13 extending downwardly from the jarm 12 into a slot 14 provided in the ar'm 11. By operation of one of these arms, a turning motion may be imparted to the two posts for adjusting the tension of the two spirals, and the friction between the pin 13' and the arm. 11 is suicient to hold the two arms in adjusted position.

The section 16 of one ofthe spirals adjacent the hinge 9 carries contacts 17 and 18 on opposite faces thereof adapted to engage with contacts 19 and 21 disposed on opposite sides of the section 16 in spaced relation to one another.

The operation of thedevice thus far described isas fol lows: If the thermostat is in tended to become active at certain maximum and minimum temperatures, the twospirals a are tensioned by operation of the plates2 vfor spacing the posts and the handles 11 and will contact the point 21, and at the minimum temperature, the section 16 will snap.

over the medial line to contact the point 19.

lt should he understood that this thermostat 1s very sensitive, due to the light structure of the spirals, while at the Sme time, it is very substantial and even rugged in its op- 5 eration, since the two loose ends of the spirals are interconnected and are thereby prevented from vibrating. will respond immediately to changes in temperature, but will not easily vibrate in response to jarring motions, and this feature would make the thermostat adapted tor use ,on moving vehicles, for instance.

The thermostat illustrated in Figures 3 and 4- is intended for liner adjustments in the spacing as well as the turning of the two posts on which the spirals are carried.

It consists of two standards 22 rising from the base 23, a horizontal rod 2li supported in the two standards and posts 25 slidable on the rods. l f v l The two posts may be advanced toward one another by means of screws 26 passing through the standards 22 and may be held in adjusted position hy means of set screws 27. An operating rod 28 extends through the two standards and the two posts and is `termed. with a suitable handle 29.

'lhe two posts 25 have pins 3l extending upwardly therefrom on which are mounted sleeves 32. These sleeves have the inner ends of the two spirals 8 fastened thereto, and the spirals are interconnected hy the hinge 9, as previously described. Each of the sleeves carries a cog wheel 33, and the two cog wheels mesh with two pinions 34 fastened on the operating rod 28.

lt will be seen that in this construction, the two sleeves holding the inner ends ot' the two spirals may he `turned by manipulating the operating rod 28, while the spacing hetween the two posts 25 may he adjnsted through manipulation of the screws 26 and 27. This app tus is capahle ot very tine adjustment will respond. to very slight chan in temperature.

lt should he understood that while the spirals sas shown in the drawing seem particular) adapted tor our purposes, particularly c .e to tact that a conside length ci metal may he accommodated small space, simuler forms 3 4iglit sulce for certain purpo s, such as sp turn, i ess than a.

made suthc" ntly res suthcient -iliency to snap tat control vneftallic ends se L ted tension @55 connection is snap across the centerline in response to changes in temperatures.

- 2. ln a thermostat control of the character described, two bimetallic lengths of spring material, two posts mounted in spaced relation, each having one end of the said lengths attached thereto so that ythe two free ends tend to overlap along the centerline of the posts, a `connection between the tree ends adapted to place the said lengths under tension, and means 'for revolvably adjusting the two posts v 3. ln a thermostat control of the character described, two bimetallic lengthsl of spring material, two posts mounted in spaced relation, each having one end of the said lengths attached thereto so that the two tree-ends tend to overlap along the centerline of the posts, a connection between the tree ends adapted to place the said lengths under tension, means for revolvably adjusting the two posts, and means *for adjusting the spacing between the two posts.

4. in a thermostat control of the character described, two bi-metallic spirals having radial outer ends, means forr mounting the inner ends ot' the spirals in spaced relation so as-to cause the outer ends to extend toward chored in 1spaced relation, said spirals having outer integral end portions bent to extend radiall'y and to substantially lie in the centerline of the anchors, a connection disposed he tween the radially extending portions, and with said portions serving to place said spirals under a compression force, whereby the radial portionsaremade to snap across the center line in response to temperature changes. REUBEN S. TCE. ARTHUR L. HLCUMT, 

